Laminated spring



April 14, 1925. 1,533,984

H. FROOD LAMINATED SPRING Filed June 2, 1924' Fig.3

Fig.4 I102) re/$0.2 Ii. .7120 0 a?) J2 ttys.

Patented Apr. 14, 1925.

,UNITED STATES- PATENT OFFICE.

HEB/BERT PROUD, OF SOVEREIGN MILLS, CHAPEL-EN-LE-FRITH, ENGLAND. I

LAMINATED srnme.

Application filed June 2,

To all whom it may cmwem;

Be it known that I, HERBERT FRoon, a subject of the King of Great B ritain'and Ireland, and resident of Smereign- Mills,

5 Chapel-en-le-Frith, in the county of Derby,

England, have invented certain new and useful Iin rovements in and Relating to Laminated prings, of which the following is a specification.

- springs for vehicles and other purposes.

-. 'It has been found that the interposition between the individual leaves of leaf springs of laminae of material other than metal which is resistant of the action of water, oil and heat and is further resistant tofriction in the sense that its desirable properties are not detrimentally affected from the wear resisting .point of view by friction due to slipping, presents numerous advantages.

The object of the present invention is to provide an improved construction of laminated or leaf spring whereby the individual leaves shall be effectively rotected from 5 moisture and the non-meta lie or friction material located between the leaves securely held in position.

According to this invention, the springcomprises metallic leaves which are individually encased in a covering of non-. N

metallic material, whih may if desired have v a metallic reinforcement.

The casings for the individual leaves may be of tubular form or may be substantially .tubular, that is to say, formed by folding.

or bending a sheet of material so as to bring two opposite edges of the sheet: substantially into contact. Alternatively, the casings may be formed by folding or bending in the manner indicated and a joint made between the abutting edges. In a further alternative, the casings may be formed without a joint in any suitable manner, for instance, by moulding a suitable com osition or by forming a tubular envelope y weaving or knitting. i a

The casings or envelopes 111% be afiixed to the leaves of the springs by vulcanizing or otherwise. a

The fibrous material employed in-the construction of the leaves may be of vegetable, animal or mineral origin, or fibrous material from any two or more of these origins may be employed conjointly. Asan example of suitable material, of. which the This invention relates to laminated or leaf 1924. Serial 1T0. 717,420.

maybe formed, we employ a combination of fibrous material such as asbestos, with an organic binder, preferably of an infusible character, for example, a combination of asbestos with infusible phenol formaldehyde condensation products, may be mentioned. Metal wires may if desire be embedded in or incorporated with the aterial of the casing for the purpose of reinforcing it.

The whole of the individual leaves of a spring may be separately encased in accordance with theinvention, but if desired the top or longest leaf may be left unencased or be encased for only a portion of its length in orderthat connection between it and other members, for instance, shackles and dumb-irons, may be facilitated.

In some cases it may be considered desirable to seal the ends of the casings of the leaves, thus completely enclosing the metal and securing it from atmospheric and other destructive agencies and if desired, lubri cant may be mtroduced into the casings or between them. The casingsmay be formed with interior surfaces constituted by un- 80 bonded fibrous material, that is to say the fibrous material or'the fabric formed. erefrom may be left in the soft or grey state, so as to act as a carrier or holder for a lubricant, as for instance, grease, oil or graphite, or an anti-rust or other composition which it may be desired to have in direct contact with the metal leaves, theoutside of the casing being of a water and wearresisting character, or possessing other properties which are desirable in a spring interleavmg. i

Referring to "the accompanying sheet of explanatory drawings Figure 1 is an elevation, Fi re 2 a plan and Fi ure 3 an elevation wit part insection, 0 alaminated or leaf spring as made in accordance with this invention.

' Figures 4. and 5 are sectional end views showing (to a larger scale) one leaf of such a 100 spring with modified forms or types of the covermgor envelope therefor.

Each metallic leaf 0 ofthe spring 18 pro- .vided with a coverin or envelope 6 of nonmetallic material as ereinbefore described. 106 In the type shown by the end sect on at Fi re athecovering or enveloping materia b 's foldednpouthe metal leaf a so as to bring the-longitudinal edges of the cover into contact or adjacent eac other, In the .1 0

form or type shown at Figure '5 the covering or enveloping. material I) is reinforced by metal wires as c embedded in or incorporated with the said material.

1. In laminated or leaf springs, a coverering for each leaf formed of non-metallic material, and metallic reinforcing material within said covering. 7

2. In laminated or leaf springs, a covering for each leaf consisting of asbestos material impregnated with infusible phenol formaldehyde condensation product.

3. In laminated or leaf springs, a covering for each leaf of. non-metallic material having the outer portion impregnated with infusible phenol formaldehyde condensation product and the inner portion unimpregnated to act as a carrier for the lubricant.

4. In laminated or leaf springs as claimed in claim 2, wherein metallic reinforcing material is embedded within the covering.

In testimony whereof I have signed my name to this specification.

I HERBERT FROOD. 

